From Dictionary to List

Question

This is a dictionary:

Dictionary<string, List<string>> Dic = new Dictionary<string, List<string>>();

I want to do the following: when I click a button the first dictionary (Dic) key and its values are copied to a list (List<string>). Click again, and the same thing happens, but this time with the next dictionary key and value.

Sorry I don't understand your question. Do you mean you want to add a list to a Dictionary? Or are you having problems with accessing the List? — hydev, Sep 07 '12 at 06:54
What about your [previous question](http://stackoverflow.com/q/12312240/961113) — Habib, Sep 07 '12 at 06:55
helping you would be much simpler if you add an example with the content of the dictionary and the contento of the list after each click... — Francesco Baruchelli, Sep 07 '12 at 08:03

score 1 · Answer 1 · answered Sep 07 '12 at 07:22

Looks like you want to create a new List<string> based on your all string elements in the dictionary's List values. You may use SelectMany to flatten it out and get a list using the following code:

Dictionary<string, List<string>> Dic = new Dictionary<string, List<string>>();
Dic.Add("1", new List<string>{"ABC","DEF","GHI"});
Dic.Add("2", new List<string>{"JKL","MNO","PQR"});
Dic.Add("3", new List<string>{"STU","VWX","YZ"});

List<string> strList = Dic.SelectMany(r => r.Value).ToList();

Where strList will contain all the string items from the dictionary in a single list.

score 0 · Answer 2 · answered Sep 07 '12 at 06:53

0

why not use ToList method?

Dictionary<string, int> dictionary = new Dictionary<string, int>();
dictionary["cat"] = 1;
dictionary["dog"] = 4;
dictionary["mouse"] = 2;
dictionary["rabbit"] = -1;

// Call ToList.
List<KeyValuePair<string, int>> list = dictionary.ToList();

// Loop over list.
foreach (KeyValuePair<string, int> pair in list)
{
    Console.WriteLine(pair.Key);
    Console.WriteLine("   {0}", pair.Value);
}

answered Sep 07 '12 at 06:53

John Woo

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i have Dictionary> Dic = new Dictionary>();------------------ no Dictionary dictionary = new Dictionary(); – Radzhab Ahvahsky Sep 07 '12 at 06:59

From Dictionary to List

2 Answers2